Functional Materials for Energy

Fluid-like electrophoretic behavior observed in a solid crystal

September 03, 2013

SEM image of gate electrodes (gold) along a manganite wire with electrophoretic model matrix overlay composed of insulating (red) and metallic (yellow) elements which shift during application of electric field. This opens and closes percolation channels along the wire.

The position of coexisting mesoscale electronic phase domains in a complex oxide is shown to be controlled with electric fields in an electrophoretic process previously only observed in liquids. This discovery has important implications to our fundamental understanding of how electronic phase competition arises and persists while opening the door to new types of resistive switching possibilities.

Manganite wires confined to scales on the order of the insulating and metallic domains residing within were biased using lateral gates near the metal-insulator transition. The results conform to a phenomenological model in which the inherent nanoscale insulating and metallic domains are rearranged through electrophoretic-like processes to open and close percolation channels. Since electronic phase competition is present in such a broad spectrum of complex materials, these findings are expected to have an impact on our understanding of many classes of materials, from high temperature superconductors to multiferroics.